26.Tom notices that he is a lot more short of breath after he finishes a 200 meter sprint than when he jogs for 3 miles. He is confused because he feels as if he should feel more tired when he runs for a much longer distance. Explain to him why it makes sense that he is indeed more short of breath after running a sprint than jogging. Make sure to explain it using your scientific knowledge of cellular respiration.

While sprinting, your cells use up a lot of oxygen in a smaller amount of time, forcing them to used lactic acid fermentation. Because your oxygen is lost quickly, you are our of breath. While steadily jogging, your cells use oxygen at a slower pace, giving them time to go through cellular respiration, which doesn't make you out of breath.

27. A scientist isolates mitochondria form human cells and places them in an acid solution. The acid penetrates the intermembranous space of the mitochondria. The scientist then notices that the mitochondria start making ATP despite the fact that he is not providing any glucose for them. How is it possible that the mitochondria are still making ATP? (Think back to what an acid is, what it releases when placed in a solution and why this would make the mitochondria synthesize ATP).

When acid is placed into the intermembranous space, it releases H+ ions. The hydrogen ions then go through ATP synthase, where ADP and a phosphate group are combined to make ATP.


28. Genetic testing reveals that baby Helen has a defective gene that results in the defective production of one of the proteins in the electron transport chain. Because of faulty instructions in her DNA, one of the proteins in her ETC is mis-shapen, and therefore it cannot perform its function as efficiently. Baby Helen is “failing to thrive” as she is having a hard time gaining weight and reaching developmental milestones. Using your knowledge of the ETC and its role in making ATP, explain why you think baby Helen is having the problems described above.

Baby Helen's channel protiens are defective, so electrons and H+ ions cannot move through them to make water and ATP in ATP synthase.


29. Compare the basic transformation of energy during photosynthesis and cellular respiration.

In photosynthesis, the chemical energy from the sun gets trasferred in to food energy, which is glucose. The formula for photosynthesis is sunlight + carbon dioxide + water --> glucose + oxygen. The energy from the sun gets absorbed by the chlorophll, goes through the electron transport chain, and gets transferred into ATP and NADPH. In the Calvin Cycle, the ATP and NADPH are used to make glucose. In cellular respiration, the chemical energy from glucose gets transferred into usable ATP energy. The formula for cellular respiration is glucose + oxygen --> ATP + water + carbon dioxide. The glucose from photosynthesis goes to the mitochondria, where it goes through glycolysis, the krebs cycle, and the electron transport chain. The engergy from glucose gets turned into usable ATP energy.

30. Describe the role of ATP in biochemical reactions. What is ATP used for in your cells? How do your cells get energy out of a molecule of ATP? How is ATP recharged?

ATP is used for all regular cell processes. It is the energy used to perform all of the actions the cells need to perform in order to survive. The cells get energy out of the molecule of ATP, by breaking off one phosphate, leaving ADP. That process releases the energy the cells need. The ATP is recharged when food energy is consumed, and another phosphate attches onto ADP, which once again becomes ATP.